1. Field
The following description relates to a dynamic spectrum management (DSM) scheme, and more specifically, to a DSM scheme for a multi-cell communication system including a plurality of cells.
2. Description of Related Art
Studies have been conducted regarding a communication system including a plurality of cells, in order to improve data transmission rate and reliability of a communication based on limited radio resources. The plurality of cells typically includes a cellular base station, a femto base station, a fixed base station or a mobile base station, a relay station, terminals, and the like.
Each of a plurality of base stations in the plurality of cells may substantially simultaneously use limited radio resources, for example, a frequency, a time, a code resource, and the like, to improve the efficient application of radio resources for communication with a corresponding terminal. Also, when the plurality of base stations substantially simultaneously communicates using the limited radio resources, various difficulties may arise, such as interference occurring in each terminal and a decrease in throughput due to the interference.
A dynamic spectrum management (DSM) scheme is proposed to reduce the difficulties due to the interference. According to a DSM scheme, each of the plurality of base stations dynamically adjusts spectrum powers to decrease interference received in other cells.
Also, an iterative water filling (IWF) scheme has been proposed to reduce a difficulty caused by interference occurring between various copper wires in a single binder, with respect to a DSM scheme that is applied to a wired Digital Subscriber Line (DSL) communication system. An IWF scheme optimizes spectrum powers of a desired signal, according to an assumption that spectrum powers of a signal transmitted from another transmitter are held static for each copper wire. Based on the IWF scheme, when a single transmitter updates the spectrum powers, spectrum powers of other transmitters are held static.
When the IWF scheme for the wired DSL communication system is applied to a wireless communication system, a plurality of cells sequentially updates spectrum powers. Accordingly, the IWF scheme for the wired DSL communication system may be difficult to implement. Also, since a given cell may perform scheduling of a plurality of users in the wireless communication system, a user scheduling may be changed in real time, presenting further difficulties in implementing the IWF scheme for the wired DSL communication system to the wireless communication system.